The results of a long-lasting research of sulphation process, which causes an essential deterioration of marble and limestone monuments in Saint Petersburg are reported. Based on a variety of field and analytical methods we can show that the decay process forming a gypsum-rich patina depends mainly on the local environment, the moisture accumulation, and is connected with the fissuring and porosity of the rock and the relief of a monument. Three main stages of gypsum-rich patina formation in the presence of microorganisms were revealed.
Frank-Kamenetskaya, Olga V.; Vlasov, Dmitrii Yu; Zelenskaya, Marina S.; Knauf, Irina V.; and Timasheva, Maryia A.
Decaying of the marble and limestone monuments in the urban environment. Case studies from Saint Petersburg, Russia,
Studia UBB Geologia
Available at: https://digitalcommons.usf.edu/geologia/vol54/iss2/art4